Uniformity and games decomposition.

We introduce the classes of uniform and non interactive games. We study appropriate projection operators over the space of games, in order to propose a novel canonical direct sum decomposition of an arbitrary game into three components, which we refer to as the uniform with zero constant, the non interactive total sum zero and the constant components. Under a natural inner product, we show that the components are orthogonal and we provide explicit expressions for the closet uniform and non interactive games to a given game. We characterize the set of its approximate equilibria in terms of the uniformly mixed and dominant strategies equilibria profiles of its closest uniform and non interactive games respectively.